import random
import string

import pytest
from helpers.cluster import ClickHouseCluster

cluster = ClickHouseCluster(__file__)

node1 = cluster.add_instance('node1', with_zookeeper=True)
node2 = cluster.add_instance('node2', with_zookeeper=True)


@pytest.fixture(scope="module")
def start_cluster():
    try:
        cluster.start()

        yield cluster
    finally:
        cluster.shutdown()

def get_compression_codec_byte(node, table_name, part_name, filename):
    cmd = "tail -c +17 /var/lib/clickhouse/data/default/{}/{}/{}.bin | od -x -N 1 | head -n 1 | awk '{{print $2}}'".format(
        table_name, part_name, filename)
    return node.exec_in_container(["bash", "-c", cmd]).strip()

CODECS_MAPPING = {
    'NONE' : '0002',
    'LZ4': '0082',
    'LZ4HC': '0082',  # not an error, same byte
    'ZSTD': '0090',
    'Multiple': '0091',
    'Delta': '0092',
    'T64': '0093',
}

def test_nested_compression_codec(start_cluster):
    for i, node in enumerate([node1, node2]):
        node.query("""
        CREATE TABLE compression_table (
            key UInt64,
            column_ok Nullable(UInt64) CODEC(Delta, LZ4),
            column_array Array(Array(UInt64)) CODEC(T64, LZ4),
            column_bad LowCardinality(Int64) CODEC(Delta)
        ) ENGINE = ReplicatedMergeTree('/t', '{}') ORDER BY tuple() PARTITION BY key
        SETTINGS min_rows_for_wide_part = 0, min_bytes_for_wide_part = 0;
        """.format(i), settings={"allow_suspicious_codecs" : "1", "allow_suspicious_low_cardinality_types" : "1"})

    node1.query("INSERT INTO compression_table VALUES (1, 1, [[77]], 32)")

    node2.query("SYSTEM SYNC REPLICA compression_table", timeout=5)

    node1.query("DETACH TABLE compression_table")
    node2.query("DETACH TABLE compression_table")

    node1.query("ATTACH TABLE compression_table")
    node2.query("ATTACH TABLE compression_table")

    for node in [node1, node2]:
        assert get_compression_codec_byte(node, "compression_table", "1_0_0_0", "column_ok") == CODECS_MAPPING['Multiple']
        assert get_compression_codec_byte(node, "compression_table", "1_0_0_0", "column_ok.null") == CODECS_MAPPING['LZ4']

        assert get_compression_codec_byte(node1, "compression_table", "1_0_0_0", "column_array") == CODECS_MAPPING['Multiple']
        assert get_compression_codec_byte(node2, "compression_table", "1_0_0_0", "column_array.size0") == CODECS_MAPPING['LZ4']
        assert get_compression_codec_byte(node2, "compression_table", "1_0_0_0", "column_array.size1") == CODECS_MAPPING['LZ4']

        assert get_compression_codec_byte(node2, "compression_table", "1_0_0_0", "column_bad.dict") == CODECS_MAPPING['Delta']
        assert get_compression_codec_byte(node1, "compression_table", "1_0_0_0", "column_bad") == CODECS_MAPPING['NONE']